The place in Georgetown where Yarrow Mamout, a freed African American slave, lived is now the site of an archaeological dig. A prayer service for Yarrow was held there Friday. (Nikki Kahn/The Washington Post)

A few feet away from the open pit of an archaeological dig in Georgetown, an imam from Senegal led a small group in an Islamic prayer service for the unusual man whose life may be reflected in the artifacts found there.

About 50 people gathered to honor the memory of Yarrow Mamout , a freed African slave who built a log house on the Dent Place property when Georgetown was still a suburban woodland.

Ebrahim Rasool , a former South African ambassador who is now a scholar at Georgetown University, said the site should be considered a shrine to honor the millions of Africans who endured slavery and to inspire others to carry on the fight for human rights.

“So what we are doing today is a most important claiming of memory: That our identity will not be shaken . . . that we have survived slavery,” Rasool said. “And we owe Yarrow Mamout that debt — to finish the process that he started and keep the dignity he established when he bought this property as a freed slave.”

Imam Papa Mboup, at right foreground, says a few words during the gathering in Georgetown. (Nikki Kahn/The Washington Post)

Members of the group, cupping their hands in prayer, joined Papa Mboup, an imam with the Zawiya of the Greater Washington area, in reciting the al-Fatiha, an opening prayer taken from the first chapter of the Koran.

Yarrow, a member of the Fulani tribe, was brought to America aboard the slave ship Elijah in June 1752. He could read and write Arabic and English, and he became a prominent figure in Georgetown after receiving his freedom. Well-known artist Charles Willson Peale painted Yarrow’s portrait. So did James Alexander Simpson, whose portrait of Yarrow hangs in the Peabody Room of the Georgetown Public Library.

“He was educated, which is very unusual for an ex-slave . . . probably better educated than 95 percent of the white Americans,” said James H. Johnston, a Bethesda lawyer who researched Yarrow. “He was very bright. He was very poetic in his way of speaking.”

Johnston, who documented Yarrow’s life in his book “From Slave Ship to Harvard: Yarrow Mamout and the History of an African American Family,” said the archaeological dig has the potential to illuminate the lives of all African slaves. It’s also probable that Yarrow’s remains are buried on the property, which he acquired in 1800, four years after he was freed. He built a log house on the plot, which was likely replaced after the Civil War by a wood-frame house that was destroyed in 2013 by a falling tree.

The city-led archaeological dig began June 16. Mia Carey, the site manager for the D.C. Historic Preservation Office, said workers have unearthed objects spanning several centuries, including pieces of ceramics, glass, marbles, two toy soldiers, an 1860 medicine bottle and the remains of a dog, its nylon collar still intact. Different occupants and activities at the site — including the building of a swimming pool — complicate efforts to untangle the archaeological record.

“It’s kind of typical of urban sites, in that it’s got a lot of ‘noise,’ ” said Charles LeeDecker, a retired archaeologist who is volunteering to help with the dig. “It’s a puzzle.”

Yarrow’s story conjures a time when Georgetown was more diverse. When Yarrow was walking Georgetown’s streets, about one-third of the population was black, the community’s population made up of slaves, freed blacks and whites. Today, the area is 80 percent white, according to city data for the Advisory Neighborhood Commission.

Yarrow’s life is unusually well documented, compared with many of the 9.6 million Africans brought to America as slaves, Johnston said. Yarrow was a body servant to Samuel Beall, a Maryland planter. Upon Beall’s death, Yarrow became the property of Beall’s son Brooke on a 2,000-acre holding near Potomac known as Beallmont.

His owner promised to grant him his freedom after Yarrow fired the bricks for his master’s new home, Johnston said. His owner died before the task was completed, but his owner’s wife granted him his freedom anyway.

Yarrow was a jack-of-all-trades and, according to his obituary, the best brickmaker in Georgetown, commanding twice the fee as white brickmakers. He also produced charcoal, wove baskets and worked the docks. He was an investor, too, having bought shares of the Columbia Bank of Georgetown.

An obituary in the Gettysburg Compiler written by Peale said that Yarrow, who died in 1823,, was buried in a corner of the garden where he prayed, facing east toward Mecca, according to Islamic practice.

Johnston said he believes that Peale painted Yarrow’s portrait not only because Yarrow was well known and perhaps a leader of the African American community, but also because he was a living rebuke to the practice of slavery.

“Peale believed that — a sort of revolutionary thought at the time — that black people and white people were equal. I mean, he did own slaves, so he was not a great liberal. . . . [But] when he came across Yarrow, who was a businessman, who was an entrepreneur — Yarrow proved it,” Johnston said. “It’s like the Rembrandt painting of Dutch burghers. Only, Peale was painting a Georgetown burgher . . . who just happens to be black.”